This paper tape fiddling made me wonder if anyone ever
made a cassette
tape interface that emitted RS232 signals and looked to the computer like
a paper tape reader/writer.
I doubt you could make a cassette interface that appeared identical to a
paper tape reader, since most paper tape readers will stop on a character
and cassettes don't
That said, there have been many cassette interfaces that were
hardware-intensive and which used a normal asynchronous serial chip. One
very common one (at least over here) is the BBC Micro. That has a 6850
chip linked to a ULA. The latter generates the baud clocks, switches the
6850 serial pins between the RS423 serial port and the cassette
circuitry, and encodes said serial stream to CUTS tones.
_Many_ years ago I built a CUTS encoder/decoder with an RS232 interface
and used it to read Basicode tapes. The encoder was a pair of counters
with a factor of 2 differnt in the division ration, one was held reset
when the TxD line was high, the other was reset wehn it was low. The
outputs were ORed toegether, they wete both clocked from the same
freqeuncy source.
The decoder was a couple of monostables (one-shots), connected in a
well-known circuit that I got from $deity-knows-where.
I even used one of hte handshake lines on the RS232 port to control a
relay wired to the remote socket o nthe cassette recorder.
-tony